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The clouds finally buggered off from Brisbane last night so I could test these fine doubles prepared by Bigjoe.
Scope and Eyepiece(s) used: Skywatcher 8" goto dob, Baader 8-24 zoom, Celestron Luminos 7mm, ES 82° 4.7mm
Magnification(s) used: 150x (Baader Zoom), 171x (celestron), 255x (ES 82°)
Seeing was pretty reasonable south of Brisbane last night, despite the glow of a very fullish moon right in my face. Stars were sharp up to 150x, but got a little grainy at higher mags.
RIGEL(Beta Orionis): Separation 9.5". Magnitude of pair AB : 0.28, 6.8.
PA 202°. What do you see?
RA 05h 15m 24s DEC -08°11' 02".
Easily split, with a the tiny faint companion at about 5 o'clock (still got to brush up on my PA skills through the dob).
31 ORIONIS: Separation of pair is 12.8". PA 88°. Mags of pair AB: 4.7, 9.7 ...An absolute GEM...Colours seen?
RA 05h 30m 38s. DEC -01°04' 52".
Easily split, with the main star appearing a golden orange and the secondary star appearing a dim blue.
RHO ORIONIS (p ): Separation 6.9". PA 62°
AB: MAGS 4.5, 8.5.. a pretty double.
RA 5h 13.1m. DEC +02° 51' 40".
Easily split, with a main golden yellow star and pale yellow companion.
SIGMA ORIONIS: (σ Orionis).... Superb.
AB Combined at Mag 3.7, is too close to separate for anyone, star C at magnitude 8.7 at a Separation of 11.6 " away from the AB pair isnt....
with two magnitude 6.6 stars, Called D and E, at separations 12.7" and 41.50" respectively from the AB pair ......so you'll actually see four coloured stars.......
What colours do you see? Lovely Struve 761 a triple also in FOV.
RA 05h 38m 45s . DEC -02° 36' 00".
AB appears to be pale yellow-white. C appears to my eyes a faint dusky red-purple colour, or it could have been grey, it was that dim. D appears to be a pale bluey-white, and E seemed to be a yellow-white.
Rough diagram hopefully attached.
ZETA ORIONIS (ALNITAK): Actually a triple! A, B, C. Near the Horsehead on the charts below, and PART OF ORIONS BELT.
PA 167°.
Magnitudes A: 1.77 , B: 3.7 , C: 9.6
Separation AB: 2.18″..... Sep to BC: 58.0"
RA 05h 41m 39s DEC -01° 56' 10"
Relatively easy split, no discernible colour that I could see.
SAIF AL JABBAH (ETA ORIONIS): PA 77°..SEPARATION 1.8"..Looks like an n on the SS charts below.
AB: Magnitudes 3.39, 4.89.
RA 04h 24m 09s DEC -02° 23' 50".
Just able to separate them at 150x, but slightly better division (if a bit softer) at 171x and 255x
32 ORIONIS: PA 44°... Separation 1.3". Brightest star just inside Orion near Bellatrix. MAGS AB: 4.23, 5.75 .
RA 05h 30m 47s DEC +05°56' 53" .
Use DAWES LIMIT for your scope as equal enough..Sep given in Eaglecreek observatory and elsewhere is wrong..not 0 .7".
Jeepers that's a tight one. Just managed a hairline split (maybe) or kissing/unsplit, with a fair bit of imagination at high mag, but if you weren't looking for it as a double you'd pass right by it. Both appeared golden from memory.
52 ORIONIS: SEPARATION 1.0" PA 220°.
Mags AB: 5.99, 6.03 ............Very, very, TOUGH, at or near 120mm aperture; needs very good seeing with aforementioned aperture...at least they are equal pairs, making it easier than otherwise using Dawes limit for your scope.
RA 05h 48m 58s DEC +06° 27' 27".
Not a chance Lance, not in a million years. Not with my gear, eyes, and seeing conditions.
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